Porcelain crown for artificial teeth.



H. SGHWEITZE PORCELAIN GROWN FOB ABTIF TEETH.

APPLICATION FILED DBO. 30, 1909.

977,557. Patented D50. 6, 1910.

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HEINRICH SGHWEITZER,

or NEW YORK, N. Y.

PORCELAIN CROWN FOR ARTIFICIAL TEETH.

Specification of Letters Patent.

Patented Dec. 6, 1910.

Application filed December 30, 1909. Serial No. 535,603.

To all whom it may concern:

Be it known that I, HEINRICH Sorrwnrrznn, a subject of the German Emperor, residing in New York, in the county of New York and State of New York, have invented an Improvement in Porcelain Crowns Useful for Artificial Teeth of which the following is a specification.

Figure l of the adjacent drawing is the lateral view of the crown. Fig. 2 illustrates a horizontal cross section taken in the height of D indicated by a broken line. Fig. 3, a horizontal cross section taken in the height of E indicated by a broken line. Fig. 4 is a vertical cross section separating the crown in an anterior and posterior half as indicated by the broken line.

This crown like other removable porcelain crowns has an opening in the bottom into which posts are cemented. In former constructions this opening at the bottom surface is very wide and in deeper, more interior parts of the crown surrounded by parallel running (cylindric) walls. The opening in the crown invented by myself is surrounded by conical walls the cone being a steep one such as found for instance in the opening of a glass bottle to which a glass stopper is ground. Its diameter is widest at the base or bottom and narrowest in the interior part of the crown. This shape is a very useful attachment surface for a post and is especially valuable for taking an impression from the opening. Around the steep conical opening this crown represents a strong porcelain body.

In order to reinforce the attachment to a post which might be entirely cast of gold my crown has along the lateral (approximal) and tongue (lingual) surfaces an encircling beveled surface in the neck region the bevel starting on top from a step A B-R S Fig. l and running inclined in an opposite direction than the conical walls of the opening, diminishing the horizontal cross sectional circular outline (Fig. 2 and Fig. 3) of the crown gradually toward the bottom.

This crown is especially useful for the attachment to posts that are cast from impressions, taken from the opening and from the place occupied by the encircling beveled surface thus restoring by gold the contour of that portion of the tooth which is missing upon the beveled surface up to the step. The fixation of the crown to the post is secured by cement.

Having fully described my invention I claim:

In a porcelain crown the combination of a conical central opening tapering toward the interior of the crown with the encircling beveled surface around the lateral and tongue surfaces of the neck of the crown commencing near the middle upon one side and extending at the base to a point near the opposite side up to a step extending along and finishing off the beveled surface substantially as described and shown and for the purpose set forth.

HEINRICH SCHWEITZER.

Witnesses:

JOHN P. DAvIs, A. H. DAVIS. 

